Radioactivity Flashcards
What can ionising radiation do?
It can remove electrons from atoms to form ions
What can be caused by gamma ray exposure?
Cell mutations which can cause cancer and destroy cells
What cakes an atomic nucleus stable?
If it does not change or break down
What do unstable nuclei emit?
They can emit aloe and beta particles, neutrons and electromagnetic radiation such as grammar rays
What makes a substance radioactive?
If they contain unstable atoms
What is the electric charge of alpha, beta and grammar rays
Alpha - +2
Beta - -1
Gamma - 0
What is background radiation and what are some examples?
It is all around us, some comes from natural sources and others from artificial. Some natural sources include -cosmic rays
- rocks and soil
- living things
What reads radiation?
Geiger - Mullen (GM) tube
What radiation is the most ionising?
Alpha
What radiation can travel the furthest?
Gamma
What happens in alpha decay?
The mass number decreases by 4
The atomic number decreases by 2
The nuclear charge decreases by 2
What happens in beta decay?
A neutron changes into a proton and a high energy electron
The proton stays in the nucleus by the electron leaves
The mass number stays the same
The atomic number increases by 1
The nuclear charge increases by 1
What happens in gamma decay?
They are a type of electromagnetic radiation so there is no change in mass or charge
It transfers energy from the nucleus
Too much energy in the nucleus so it releases gamma radiation
What is half life?
The time it takes for a sample to decay
What does radioactive decay do?
It reduces the number of unstable nucleus
What is nuclear fission?
Another work for splitting an atom
The process of splitting a nucleus is called nuclear fission
What is nuclear fusion?
The combining of an atom
Why would you use fusion?
- abundant fuels
- clean
- safe
- less radioactive waste
- no weapon material produced
What do control rods absorb?
Neutrons
What are safety issues of a nuclear reactor?
Needs to be shielded to prevent radiation leaking out
Radioactive gas and dust needs to be contained
Used file can contain highly active decay products with long half lives
What are some protection methods?
Dense materials
Don’t build houses near by
Stable enviroment
high security
What is irradiation and what can it do?
Exposing objects to beams of radiation
This can damage cells
Can be used for sterilising medical equipment
Not radioactive after exposure
What is contamination?
It occurs if an object has a radioactive material introduced to it
Once contaminated the radiation cannot be blocked
